English English language Etymology Spelling Usage Word origin

Collocation colocation co-location

Q: In the architectural industry, two or more firms or agencies often work together in a shared office. Depending on who is doing the writing, the firms are “collocated,” “colocated,” or
“co-located.” Which is correct?

 A: We can see why you’re confused. We were too a few months ago when we answered a similar question. But we’ve looked into this more closely since then.

What’s going on here is the messy birth of a new usage among technocrats, bureaucrats, and other crats who prefer insider language to plain English.

You’re witnessing the appearance of either a new sense of “collocate,” an old verb that means to set in place, or a relatively new word spelled “colocate” or “co-locate” that means to share a location.

Although you won’t find the new usage in the Oxford English Dictionary, four standard dictionaries—two American and two British—already have entries for a new verb, but they don’t agree on how to spell it.

Merriam-Webster’s Dictionary of English Usage (11th ed.) describes “colocate” as a transitive verb (one with a direct object) that primarily means “to place (two or more units) close together so as to share common facilities.”

But The Random House Webster’s Unabridged Dictionary, which has a similar definition, lists “colocate” as the principal spelling and “co-locate” as a variant, and it says the verb can be either transitive or intransitive (without a direct object).

The Collins English Dictionary, a British reference, agrees with Merriam-Webster’s that the verb is transitive and spelled “colocate.”

But the Oxford Dictionaries website spells it “colocate” in American English and “co-locate” in British English. For Yanks, the sharing of a location is “with someone (or something) else.” For Brits, it’s only “with something else.” The verb is intransitive, though, on both sides of the Atlantic, according to Oxford.

Is your head swimming yet? Wait, there’s more.

A bit of googling finds that all three words (“collocate,” “colocate,” and “co-locate”) are being used in the new sense of several people or things sharing a site, sometimes transitively and sometimes intransitively.

Although “collocate” is the most popular overall in searches that include both the old and new meanings, “colocate” and
“co-locate” seem to be used more often in the new sharing sense.

Our Google searches suggest that the new usage is especially popular at data centers, where it’s used to refer to the housing of multiple servers at one site.

Here’s an example from the website of Mosaic Data Services: “When downtime is not an option, Mosaic’s fully redundant Datacenter facilities are the perfect place to colocate and host your business’ critical servers and related server hardware.”

But this usage is also widely seen in the military and the business world in reference to sharing a site.

Here’s an example from the website of the US Navy’s Military Sealift Command: “MSC relocated to Singapore in order to collocate with Commander, Task Force 73.”

And here are a few recent business examples:

An article in the July 2013 issue of Vending Times says the Healthy Beverage Expo in Las Vegas “was collocated with the World Tea Expo, and the combined conferences attracted nearly 5,000 participants from more than 50 countries.”

A July 15, 2013, headline on describes the decision of two Florida fire departments to share space: “Brevard County, Palm Bay Fire Departments Co-Locate.”  

And a July 24, 2013, item in Security Systems News reports that DTT Surveillance has hundreds of customers “in places where a convenience store is colocated with a McDonalds or other fast food stores.”

We don’t like this jargony term. We’d prefer “So-and-so shared a space (or site or facility) with XYZ Co.” But if you need to use it to communicate at work, you don’t have a choice.

So which spelling is correct? You’ll have to check back in a few years for a definitive answer. This new usage is a work in progress.

For the time being, though, you might as well go along with whatever spelling is preferred in your place of work. If there’s no preference, go with “colocate,” the most common spelling in standard dictionaries.

You didn’t ask, but dictionaries say “colocate” and “co-locate” are pronounced coh-LOW-cate, while the older “collocate” is pronounced CAHL-uh-cate. We imagine, however, that people using “collocate” in the new sense pronounce it coh-LOW-cate too, as if to stress the notion of a “co-” (together) prefix.

We should mention here that the ultimate source of all these words is the Latin col- (together) plus locare (to place).

The verb “collocate,” which first showed up in English in the 16th century, is transitive and usually means to set in place, place side by side, or arrange, according to the OED.

However, a specialized meaning in linguistics showed up in the mid-20th century: “To place (a word) with (another word) so as to form a collocation.”

What, you may ask, is a linguistic collocation? It’s two or more words that often appear together: “green” and “envy” … “horse” and “sense” … “addled” and “brain.”

And with that, we’ll call it quits before our brains get any more addled.

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